1. Field of Invention
This invention generally relates to learning user preferences and, more specifically, to using those preferences to personalize the user's interaction with various service providers and interactions with content query systems, e.g., to better find results to queries provided by the user and to ordering the results for presentation to the user.
2. Description of Related Art
Personalization strategies to improve user experience can be chronologically classified into two categories: (1) collaborative filtering and (2) content reordering. Each is summarized in turn.
Collaborative Filtering was used in the late 1990s to generate recommendations for users. The term collaborative filtering refers to clustering users with similar interests and offering recommendations to users in the cluster based on the habits of the other users. Two distinct filtering techniques—user based and item based—are used in filtering.
In U.S. Patent App. Pub. No. 2005/0240580, Zamir et al. describe a personalization approach for reordering search queries based on the user's preferences. The application describes a technique for learning the user's preferences and increasing the promotion level of a search result based on personalization. Zamir et al. create a user profile, which is a list of keywords and categories listing the user preferences. The profile is generated from multiple sources, such as (1) information provided by the user at the time the user registers a login, (2) information from queries that the user has submitted in the past, and (3) information from web pages the user has selected.
Some systems directed to reordering content in the context of television schedules define categories and sub-categories according to an accepted standard. User preferences are gathered using various models such as (1) user input, (2) stereotypical user models, and (3) unobtrusive observation of user viewing habits. In some implementations, these models operate in parallel and collect the user preference information.
In other systems, a set of fixed attributes is defined and all media content and all user preferences are classified using these attributes. A vector of attribute weights captures the media content and the user preferences. The systems then determine the vector product between the content vector and the user preferences vector. The system suggests content to users where the values of the vector products exceed a predetermined threshold.